Scaffold structure



M 1961 G. P. HOLLINGSWORTH 2,985,253

SCAFFOLD STRUCTURE Filed Sept. 22, 1958 2 Sheets-Sheet 2 INVENTORATTORNEK SCAFFOLD STRUCTURE George P. Hollingsworth, 1205 W. 47th St.,Kansas City, Mo.

Filed Sept. 22, 1958, Ser. No. 762,567

3 Claims. (Cl. 182-17) This invention relates broadly to the fieldof'building repair operations, and refers more specifically to novelscaffold structure which obviates the need for a space consumingmultitude of expensive units that must be placed in position prior tothe beginning of the repair operation.

In the past when it has been necessary to carry out repair orconstructions at a substantial distance above the ground floor, it hasbeen common to erect or fabricate expensive and space consuming scaffoldstructures to provide a platform for the workmen so that they may reachvarious areas at relatively high levels. Such scaffold structures havebeen necessary in work which is conducted within a high ceilingedbuilding, or on the outside of such buildings when it is desired to workon the outside of the building at relatively high points on the Wallsthereof. The problem is especially acute in the repair or constructionof areas Within a high ceilinged building because of the fact thatsubstantially the entire fioor area of the building must be. filled withthe scaffold structure in order that the workmen may have access to andfreedom of movement with respect to the entire ceiling and areas of thewalls adjacent thereto. Scaffolds of this type are quite expensive topurchase or lease and require considerable manpower and time to erect.

It is one of the important objects of the present invention to providescaffold structure which can be placed in position either within abuilding or adjacent the outside wall thereof in a minimum of time andwith a very small number of components being required, and which isuniversally adapted for all conditions which require a scaffold byvirtue of the fact that it is provided with movable stages whereby it isnecessary to provide upright scaffolding only along two opposedlongitudinal walls of the room, or adjacent one external wall of thebuilding, thus leaving the central portion of the room or the lowerareas of the external wall completely free for other operations.

The invention contemplates the provision of scaffold constructionwherein the upright scatfolding along opposed walls of the room isconstructed to receive longitudinal shiftable carriages which are inturn constructed to support and firmly secure thereto an elongated stageextending across the width of the room under construction or repair tothe end that the stage may be shifted across the roomalong the scaffoldassemblies, thus to permit a workman on a stage to reach any portion ofthe ceiling or wall surrounding the ceiling without. intricateintermediate scaffold structures being necessary, and without requiringreplacement of or shifting of the upright scaffolding.

A further important object of the, invention issto provide a stageconstruction which can beused interchangeablyas a carriage supportingstructure .or stage, thus adding materially to, theuniversality ofapplication of, the systern and reducing the number of components whichmust: be purchased orleasedfor any given job; i Still another object ofthe invention is to provide scaf- Stfltes Patent fold construction ofthe character described wherein the stage supporting carriages includereleasable means for fixing the carriages in a selected positionrelative-the upright scaffolding or the carriage supporting memberswhereby to eliminate the danger of the stage shifting while a workman isstanding or moving about on the stage.

Other important objects of the invention relate to the provision of aconstruction wherein the connection between the carriages and thesupporting members therefor is one in which there is no danger of thecarriages accidentally tipping free therefrom, but in which shifting ofthe carriages is accomplished with speed and facility; and to theprovision of means on each of the carriages for releasably attachingthereto the stage so the accidental displacement of the stage from thecarriage is effectively prevented, yet which permits ready disassemblywhen desired.

Other and further objects of the invention together with the features ofnovelty appurtenant thereto will appear in the course of the followingdescription.

In the accompanying drawings which form a part of the instantspecificationand are to be read in conjunction therewith, and in whichlike reference numerals indicate like parts in the various views:

Fig. l is a plan view of a preferred form of the instant inventionillustrating three interconnected stages, one stage transverse to theother two and movably supportedthereon by the carriages of theinvention;

Fig. 2 is a fragmentary side elevation of the embodimerit of thestructure illustrated in Fig. 1; a I

Fig. 3 is an enlarged fragmentaryview taken generally along the line 33of Fig. 1 in the direction of the arrows; I

Fig. 4 is an enlarged fragmentary view taken generally along the line 44of Fig. 1 in the direction of the arrows; I

Fig. 5 is-an enlarged fragmentary and partially sectional view of thebrake mechanism from a similar position as resulted in Fig. 4;

Fig. 6 is a view taken along the line 6-6 of Fig. 5 in.

the direction of the arrows;

Fig.7 is an end elevation of a scaffold construction embodying theconcepts of the invention and illustrating a modified form of stage,including means for supporting workers at different levels from the samecarriages;

Fig. 8 is a view taken generally along the line 8-8 of Fig. 7 in thedirection of the arrows, and

Fig.9 is a perspective view of the clamping bar disassociated from thecarriage.

As heretofore pointed out, the present invention has particularapplicability to use within high ceilinged rooms or areas andconsequently I haveshown in Figs. 1 and-2 portions of an arrangementdesigned for this purpose. The general arrangement encompasses a pair ofelongated members broadly designated by reference numeral 10 which .aredisposed in spacedparallel relationship and at some distance from oneanother as indicated by the break lines.

Each of the members 10 is supported in turn in an elevated. position byupright scaffolding towers 122 which maybe conventional inform, it beingnecessary only that towers 12 be so located as to support the elongatemembers 10 in parallel and equally spaced relationship. Each of themembers it) includes a pair of equally spaced substantially parallelchannels 13 and 14, each provided witha pair of parallel flanges 1'5 and16 and a web 17 interconnecting the flanges.

shown in Figs. 1 and 4, spaced cross braces 18 rigidly interconnectcorresponding webs 17 of the spaced channel members and serve tomaintain the channels in correct parallel relationship. In order toprovide sup- RD port for workmen permitting movement along and directlyupon the members a floor is provided between the channels of the members10 in the form of planks 19 which may be constructed of wood or lightmetals or other suitable materials. These planks are preferably screwedto the cross braces by metal screws 20, although obviously otherconnecting means may be employed.

Bridging across and supported at its respective ends upon the members 10is a third stage member S, preferably identical to members 19. However,it may be any conventional stage having the requisite physical strengthto support workmen intermediate its ends when supported only at theends.

It will be observed that the transverse stage S is actually supported onthe parallel stages by means of intervening carriages 21, one of saidcarriages mounted on each of the members 10 for longitudinal movementtherealong. Each of the carriages Z1 is substantially U-shaped intransverse section, as is clearly illustrated in Fig. 4, having a pairof spaced parallel normally upright side frames 22 and 23 and an upperframe 24 interconnecting side frames at their upper ends; Upper frame 24presents a substantially flat surface adapted for receiving thetransverse stage member 10.

Each of the side frames 23 and 24 includes a pair of substantiallytriangular truss sections, each of which is provided with a roller orwheel 26 rotatably mounted on the lower apex thereof by means of stubaxles 27. Thus, it will be observed that there are at least four rollersor wheels 26 which are rotatably mounted by the axles 27 oncorresponding corner portions of the side frames. As illustrated in Fig.4, axles 27 extend inwardly from the side frames 23 and 24 so that therollers 26 are located between the side frames and are disposed withinthe channels 13 and 14 between the flanges thereof. The members 10 arethus track members for the carriages.

The transverse stage member S is clamped firmly to the respectivecarriages 21, in each case by a clamping bar 30. Each bar 30 is pivotedabout one vertical post 32 rising from the carriage. Post 32 is threadedover a considerable portion of length and the bar is retained in oneselected position on the post by retaining nuts 33 and 34 which sandwichthe bar therebetween and which are, of course, adjustable upwardly anddownwardly on the post to accommodate the bar to different levels abovethe carriage. Preferably post 32 is also pivoted about a horizontal axisas by bolt 35 which connects it to the carriage.

A second post 36, identical in all respects to post 32, is located onthe opposite side of the carriage and is likewise pivoted at its lowerend to the carriage as at 37. The resistance to rotation provided in thepivotal connection should be sufiicient that post 36 will normally standupright unaided. The bar 30 is releasably connected with post 36 bymeans of a lateral notch or recess 36a in the bar (see Fig. 9). Clampingnuts 38 and 39 lie on opposite sides of the bar and ordinarily firmlysecure the bar to the post. However, it will be evident that the bar canbe disconnected from post 36 by simply loosening the upper nut 38 andswinging the bar away from the post.

The pivotal mounting of post 32 on the carriage has an important objectin that when the bar 30 is disconnected from post 36 as above described,the bar can be pivoted upwardly away from the stage S as shown in brokenlines in Fig. 2, thus making it considerably easier to handle the stageS, place it in position on the carriage and remove it therefrom.

Preferably the upper retaining nuts 33 and 38 on posts 30 and 36,respectively, are of a diameter sutficient to facilitate handmanipulation and may be knurled or fluted so that a good grip can beobtained and maintained.

Each carriage is provided with at least one locking mechanism (generallyindicated at 40) which is operable to lock the carriage against furthermovement along its track member at any selected position therealong. Thelocking mechanism illustrated comprises a pair of jaws 41 and 42 forminga part of a scissors-like clamping arrangement. The jaws are arranged tolie respectively above and below the upper flange 17 of the track andare pivoted about a shaft 43 extending from and firmly secured to thecarriage. To alternately cause the jaws to firmly clamp the flange orrelease it as desired by the workmen, there is provided a thrust screw44 having threaded connection with jaw 41 and extending freely through asmooth and slightly tapered aperture 42a in the jaw 42. A collar 44abelow jaw 41 and an enlarged head 44b above the jaw 41 cooperate toprevent longitudinal movement of the thrust screw relative thereto. Thehead 44b is apertured to receive a lever bar 45 which provides a meansfor rotating the screw to open and close the jaws as desired.

Preferably the pitch of the threads on thrust screw 44 is high enoughthat the jaws can be firmly clamped and released within the scope ofless than one complete revolution of the lever 45. a

The operation and manner of use of the invention as described thus faris believed evident from the foregoing description. In the case ofrepair operations being conducted in a room, the towers 12 are locatedon opposite sides of the room and the track members 10 placed inposition thereon adjacent the walls and at substantially the sameelevation. Thereupon a carriage 21 is placed upon each of the-trackmembers by running rollers 25 into the open ends of the channels 13 and14, and the carriages are fixed in position by the manipulation of thelocking mechanism 40 previously described. The transverse stage S isplaced in position upon the carriages and tied thereto by bars 30.

It is obvious that the stage S can be moved to any position desired fromone end of the track members to the other, thus making it possible tolocate the stage at any intermediate position between the walls. Theflooring on the tracks 10 provides standing space for workmen whileworking on those walls or when releasing the carriages for movementalong the track members. The great advantage in the arrangement is thatthe center area of the room is left completely free of any scaffoldingstructures and yet the workmen may, by shifting stage S, have access toany portion of the ceiling.

A modification of the invention is illustrated in Figs.

7 and 8 wherein it can be seen that a stepped bracket,

broadly designated 101, is suitably secured to the lowermost space ofthe stage S. Stepped bracket 101 is preferably constructed of a singlelength of bar material which is bent to present a series of steps 192interconnected by risers 103. Steps 102 are preferably positioned so asto be horizontal with the ground or floor when stage S is disposed'uponcarriages 21. There are actually two brackets 101 secured to stage S anddepending therefrom. Preferably the steps 101 of the bracket are ofsuficient width to receive a supplemental stage plank S which is intransverse relationship to the main stage S. In this manner either oneor a number of secondary stages S may be placed in position upon steps102 in transverse relation to the main stage S and at any one ofpredetermined elevations relative to stage S.

I Thus a workman may work on various portions of the ceilingor the like,which are normally lower at the corners thereof, without the necessityof lowering the elevation of the track members and Without the necessityof his bending over during the time it is necessary for him to work onthe lower area. The invention as modified is particularly suitable forrepair work 'on pitched It will be understood that certain features andsubcombinations are of utility and may be employed without reference toother features and subcombinations. This is contemplated by and iswithin the scope of the claims.

As many possible embodiments may be made of the invention withoutdeparting from the scope thereof, it is to be understood that all matterherein set forth or shown in the accompanying drawings is to beinterpreted as illustrative and not in a limiting sense.

Having thus described my invention, I claim:

1. In a scaffold system providing elevated working surfaces, thecombination of two pairs of spaced towers, a pair of elongate platformmembers bridging the upper ends of the respective pairs of towers, theplatform members being disposed in spaced parallel relation and eachproviding a walkway between the towers which it bridges, track memberscarried by each platform member and running lengthwise thereof, a pairof mobile carriages on each platform member, each carriage having wheelsengaging the track members and movable longitudinally thereof todifferent positions relative the towers, an elongate stage, and meansfor releasably securing the stage to the carriages in transverselyextending relationship with said platform members.

2. In a scaffold system as in claim 1, the inclusion of means on eachcarriage for releasably securing the same to its platform member at anylocation therealong.

3. In a scaffold system as in claim 1, said track members being disposedbelow the level of the upper surfaces of said platform members wherebyto provide a level working and walking surface on the platform members.

References Cited in the file of this patent UNITED STATES PATENTS1,593,945 Macklem July 27, 1926 1,740,117 Pinckey Dec. 17, 19291,863,984 Hoelfeldt-Lund June 21, 1932 1,918,905 Grimm July 18, 19332,072,354- Biebel Mar. 2, 1937 2,623,614 Herr Dec. 30, 1952

